394 MR. G. E. DOBSON ON THE [Mar. 1, 



Serratus posticus is very largely developed ; it arises by an 

 aponeurosis from the posterior (bird of the ligamentum nuchfe, from 

 the first two or three dorsal spines, and from the fascia of the back, 

 and is inserted into all the ribs with the exception of the first three. 

 Berratus magnus is also very large, consisting of a cervical and a 

 thoracic portion, the former the united levator anguli scapulce. 

 There is no distinct uplenius colli. The trachelo-mastoid is large, 

 arising by a thin muscular aponeurosis from the anterior three or 

 four dorsal transverse processes in close connexion with the origin of 

 the transversalis cervicis, also from the sixth, fifth, and fourth 

 cervical transverse processes, and converges to form a short tendon 

 which is inserted into the mastoid process. 



Complexus tertius, from the articular processes of the sixth to 

 the third cervical vertebrae, is in intimate connexion with the attach- 

 ment of the complexus mnjor, which lies internal to it, and is 

 inserted into the extremity of the transverse process of the atlas. 

 Scalenus medius et posticus are united, forming a large muscular 

 mass, which arises from the transverse processes of the cervical 

 vertebrie above the brachial plexus which separates it from the 

 longtis colli. The longus colli appears to commence from the body 

 ot the seventh dorsal vertebra (but small muscular fibres may be 

 traced from the body of one vertebra to the other as far back as the 

 diaphragm), and passes forwards from the body of one to the inferior 

 lamellae of the transverse process of the next, until it finally ter- 

 minates at the atlas. 



Jiectus abdominis et sternalis is well developed throughout its 

 whole length, extending from t!ie first rib to the pelvic bones. The 

 attachment of this pair of muscles to the latter is very peculiar, 

 namely by four interlaced fleshy tendons ; the left rectus divides 

 about midway between the umbilicus and the symphysis pubis into 

 a pair of fleshy tendons, which are directed backwards and outwards 

 towards the right pubic bone, and go between a corresponding pair 

 from the right rectus, passing towards the left pubic bone in such a 

 manner that the internal division of the left rectus is superficial. This 

 division is narrower than the others, and tendinous at its insertion. 



This interlacement of the tendons of the recti forms a powerful 

 support to the weak and narrow symphysis of the pubic bones, which 

 must be se])arated at the time of parturition, as the extremely narrow 

 diameter of the pelvis (referred to above, p. 390) is evidently quite 

 insufficient to admit of the passage of the foetus. It would also 

 effectually prevent rupture of the abdominal walls in a vertical 

 direction when the symphysis is widely separated, and ensure re- 

 apposition of the pubic bones. 



There are no distinct linece transversce ; the obliqui externi unite 

 muscularly along the middle line between the sternum and the 

 umbilicus; the obliqui interni are exceedingly thin and aponeurotic, 

 which is also the condition of the former muscles behind the um- 

 bilicus, their places as supporters of the abdominal walls being 

 evidently taken to a great extent by the cutaneous muscles, the 

 humero-abdominales , and by the recti. 



